Support is requested for continuation of an intensive one-week Summer Workshop to be held in Snowmass, Colorado, initiated in 1978, on the biology and histopathology of neoplasia for graduate students, postdoctoral trainees, and a limited number of senior scientists engaged in basic cancer research. Many investigators in the cancer field, particularly those working in the area of molecular biology, have had little exposure to the biology and pathology of human cancer. The purpose of the Workshop is to provide the students with a unique training experience in cancer biology, pathology, and related disciplines to enable them to pursue avenues of investigation that will contribute to our understanding of the etiology, treatment, diagnosis, and prevention of cancer. The American Association for Cancer Research considers this Workshop to be an essential training opportunity for young basic researchers who are in training because it provides the broad overview of the problem of human cancer that they need to bring their specialized investigations to fruition. The Workshop program is developed by its faculty, a group of cancer researchers working in tumor biology, pathology, and other appropriate scientific disciplines at a variety of institutions in the United States. The Workshop program is reviewed by the distinguished scientists who serve on the Board of Directors and the Special Conferences Committee of the AACR, a scientific society of 20,000 members worldwide working in all aspects of basic, clinical, and translational cancer research. Each session is evaluated by a student survey, and the collective comments of the students are utilized to institute any necessary changes or updates in course content for the following year. A pre-/post-test is utilized each year, and a long-term Student Survey of attendees from 1996-2000 was recently completed. The results of the test and survey have shown that significant learning has occurred at the Workshop and that most students feel that the Workhop is valubable and helps advance their careers. The AACR's experienced staff administers the Workshop; it is able to bring to this program not only its ten years of experience with the current project, but also an excellent track record in the operation of two similar educational programs (also funded by the NCI) which take place every Summer.